Damping and lift device for outboard motors



Oc't. 10, 1961 E. c. KIEKHAEFER DAMPING AND LIFT DEVICE FOR OUTBOARD MOTORS 2 Sheets-Shes? 1 Filed Aug. 5, 1960 INV EN TOR. Elmer C. Ife/(haefr Andru; Sfar/(e affini-nys Oct. 10, 1961 E. c. KIEKHAEFER OAMPING AND LIFT DEVICE FOR OUTBOARD MOTORS Filed Aug. 5, 1960 2 Sheer.s. sheet 2 @Maxam/w a ONU n' N K C d .a Mw mw United States Patent O 3,003,724 DAMPING AND LIFI DEVICE FOR OUTBOARD MOTORS Elmer Carl Kiekhaefer, Cedarburg, Wis. v (2408 Cypress Gardens Road, Winter Haven, Fla.) Filed Aug. 5, 1960, Ser. No. 47,744 9 Claims. (Cl. 248-4) This invention relates to an outboard propulsion unit supported to tilt about a horizontal transverse pivotal axis and more particularly to such a unit provided with damping means adapted for damping the angular momentum of the tilting unit about the pivotal axis md selectively raising and lowering the propulsion unit.

'Ille support bracket means for relatively large high powered outboard propulsion units such as outboard motors, are frequently equipped with damping means, such as shock absorbers. The `damping means serve to damp the angular momentum of the propulsion unit as when the unit strikes a submerged or floating object and thus prevent possible damage -to the unit and/or boat transom to which the unit is secured by the impacts of the swinging propulsion u nit against its mounting bracket.

The support bracket means for such propulsion units are also frequently equipped with power means for selectively tilting the unit on its transverse axis to a raised inoperative position with the lower portion of the unit out of the water and for returning the same to its running position in the Water. When the propulsion unit is not equipped with power means for tilting the unit, it is necessary to manually raise the unit when desired. For propulsion units weighing as much as several hundred pounds, this is diicult and especially for one person.

. In accordance with this invention au hydraulic damping means is interposed and connected between the pivotal outboard propulsion unit and its lmounting bracket for damping the angular momentum of -the tilting unit in either or both the upward or downward directions of pivot as when striking a submerged or oating object. A source of hydraulic pressure communicates with the damp-` ing means through a pressure line and is adapted to pressurize the damping means when desired to pivot the propulsion unit-to a raised inoperative position. Means in the pressure line provide for relieving the pressure in the damping means and thereby provide for the return of the propulsion unit to its operative position in the water.

The accompanying drawings illustrate the best mode for carrying out the invention as presently contemplated and set forth hereinafter.

ln -the drawings:

FIG. l is a side elevation of an outboard motor mounted on the transom of a boat, partially shown, and shows the hydraulic dual function damping means of this invention and in broken lines shows the motor in a partially raised position;

, FIG. 2 is an enlarged perspective sectionad View of a damping means adapted to serve a dual function in accordance with this invention;

FIG. 3 is an enlarged diagrammatic view of the control mechanism for the damping means whereby to effect raising and lowering of the motor unit as desired;

FIG. 4 is a diagrammatic view showing another embodiment of a control mechanism for `the dual Vfunction damping means; and i FIG. 5 is a perspective view and shows how the invention might be utilized for an outboard propulsion unit having an inboard drive source, not shown.

Referring to the drawings, the motor unit 1 of the outboard motor includes an engine, not shown, enclosed within a cowl 2 supported on the hollow drive shaft housing 3. The housing 3 encloses a drive shaft, not

3,003,724 Patented Oct. 10, 1961 rice propeller 4 carried by the lower unit 5. The motor unit 1 is fastened pendently and dirigibly to the transom 6 of a boat 7, only partially shown, by suspension means including a clamp'bracket 8 and a swivel bracket 9.

The clamp bracket 8 is an inverted C-clamp structure which is adapted to engage over the edge of transom 6 to place the spaced legs thereof on opposed sides of the transom. 'Ihe inner leg of bracket 8 carries one or more clamp screws 10 adapted to engage-the inside of the transom and thereby securely clamp lthe bracket 8 to the transom. The outer leg Yof bracket 8 is provided with a rearwardly projecting portion` 11 having spaced openings `1?. adapted to selectively receive a tilt adjustment pin 13 normally engaged by the motor unit in service for positioning the motor unit at a desired operating position with respect to the vertical.

The swivel bracket 9 of the attachment means is pivotally connected to the clamp bracket 8 by means of the transverse horizontal tilt pin E14 to 'provide for tilting of the motor unit on a horizontal axis. The swivel bracket 9 carries the motor unit by means of the generally vertical swivelpin 15 which extends through the bracket 9 and lis pivotal Vtherein to provide for steering control of the motor unit.

According to this invention, damping means are interposed and connected between the clamp bracket 8 and swivel bracket 9 and serve the dual function of damping the angular momentum of the tilting or swinging motor as when the lower unit strikes an obstruction and of hydraulically raising the lower unit when desired.

As shown in the drawings, the damping means comprise one or more shock absorber units 16 as shown most clearly in FIG. 2. lThe shock absorber unit 16 includes the pressure cylinder 17 closed by endV members 18 and 19, respectively, and filled with an hydraulic uid such as oil. A piston 20 is slidably disposed within the cylinder 17 and is secured to one end of the rod 21 which extends coaxially of the cylinder and through guide plug 22 and outwardly through an opening 23 in the end member 19. A sealing member 24 surrounds the rod 21 and is maintained in sealing engagement with the rod and end member by the coil spring 2S abutting on yguide plug 22.

The piston 20 of shock absorber unit 16 is provided with a stepped leading surface 26 with the inner portion of increased thickness being provided with an opening 27 coaxially thereof. The piston is carried by the rod 21 with the reduced diameter end portion thereof extending through opening 27 and with the trailing surface 28 of the piston resting on shoulder 29 of the rod. A plurality of circumferentially spaced orifices 30 extend through the piston and provide for restricted ow through the piston to provide damping as the piston moves within the cylinder when the shock absorber is extended or contracted. A plurality of circumferentially spaced stepped valve orifices 31 also extend through the piston with the larger bore openings being in the leading surface 26. The shoulders 32 within the stepped orifices 30 form seats for the ball valves 33. A relief spring 34 exerts a given force on each ball 33 and is retained within orice 31 by means of -the spring retaining Washer 35 disposed on rod 21 adjacent the leading surface 26 of the piston. The nut 36 threaded on the end of rod 21 secures the piston on the rod between shoulder 29 and the retaining washer 35. The spring-loaded ball valves 33 serve as relief valves at a given pressure to produce a desired amount of damping for the stroke of the piston upon extension of the shown, which. drivingly connects the engine and 4the shock absorber.

A pressure line which is further described hereinafter communicates with the shock absorber unit 16 ahead of piston 20. The pressure line comprises a flexible conduit 37 having a tting 38 on theend thereof which is adapted tienuf the shock absorber, the amount et damping result:

ing from the pStQn strlse is 'derenent' upon the resistanceencountered by thepiston as theuid escapes ahead thereof into the conduit 37, andY through theforiiices tothe rear of the, piston, 4

` The shockY absorber '16. further ineludes means. fur.

mounting the unit between thel 612mb.' 'ibreket '8. and. swivelbracket; 9fof the. motor suspensionj VAn end` rin'g' 4Q is fprovided onend member the'.shock absorber4 and is adapted tolbepivotally on.` the,'transverse` pin member 41 on swivel bracket 9;. AtA the o1`9p'ose-dx'end,l

o'fithe shock absorber 16, the ring member 42f'provide'df on the outer end of piston rod 2.1 is adapted to beV pivotally seeuredon thejtransverse pinmeniber 43 which is disposed beneath pinlmember V41011 the outer leg of clamp bracket 8; So disposed and connected within the motor suspension, shock absorber 16 is extended and contracted with swinging or tiltingmovement yof. the motor unit about the transverse tilt pin 14 to dampthe angular momentum of the unit andthereby greatly reduce'the severity ofI the impacts at the top and bottom' of, the motor. swing.V

When connected to a suitable hydraulic system, the shock absorber y16 is also adapted to servepae means for raising the motor unit to a tilted position whenvdefsired. i

According to FIG. 1, the exible'conduit l37T Aopposite from the shock absorber isfconnected to a remote'con'-L trol unit 44. The pressure conduit Sjmay be interrupted by an adaptor tting 45- mounted on thejcowl 2 of theA motorunit, as shown, tosu'pportthe conduit and vthereby prevent foulingv ofthe pressure line Vwhen ther motorunit" is tilted. The adaptoriittingS further prior/ideas.adis-` absorber and thereby tilt or pivot the motor unit to a raised, inoperative position. When it is desired to return the motor unit to its operative position, the handle member 53 and valve member 50 are simply returned to their initial position. The return ofv handle member 53 to its initial, position.` permitslthe motor1 switch SJS... t.o. .oper,ry and thereby' shuts'oi the pumpmuv and places the reservoir Y, return 11'ne49 inV communication. with; the line 37 to the connectmeans whereby thercontrolunit 44mayf`be re- Y moved ,from the motor unit if and. when desired.

The vcontrol unit 44, shown diagrammaticallyin FIG. 3, comprises a pressure supply mechanism and includes the selector valve 46 which*communicateswithV theshock absorberl through conduit 37. '[hevvalve'46,k also com-Y municates with a reservoirI 47 .of `hydraulic fluid through a supply line 48 anda returnline 4 9. The rotatable member 50 of-Valve 46 is provided with;intersecting'pas-Y sages'Sl and 52.which arerradaptedV to seleptivelyu'place either the supply line 48 or return line 49 from the .reser voir 47 in communication with pressure line 37 in accordance with operation of the controlhandle 53 which extends outwardly of 4valve 46 xfrom memberfG through the opening 54.

A pumpSS operated by motor 56.uisdi sposed in the supply line 48 and is adapted to develop the pressures needed to extend the shock absorber 16. TheA pump motor 56`is runoi of battery 57 and is controlledby switch 58 which is engageable by the vcontrol handle 53 to start and operate the motor`56when the valvemember is rotatedl to place theI reservoir. Supply line 48-V in communication withthe line 37.z

The control handle 53.for operating the rotatable valve member v5() has buttwo positionsancl is nornllly dis.-y posedto place the reservoirpreturn line 19in icornmur'iica.-v tion withI line 37to the shockabsorber and outof engagement with motor swith,y 581 as shownin FIG. 3. In this positionY of the handle.53 and valve'member/SG, the shock absorber"16 cany damp the angular momentum of the tilting motor unit as causedwhen` the motor unit hits a floating or'submerged obstruction inservice.

When it is desired .to raise 4or` tilt the -motorfunitrto an inoperative position, thevhandler'member 53 is actuated to rotatev the Valve member'jto place thex reservoir supply line 48 in communication with line 37l to the shook absorber. At the end of the strokeA of the handle member "53, the motor switch 58 closed byvenga'g'emext with handle member 53 placing pump 55'in 'operation to produce the nece'ssary'pressure'V inthe shockabs'orber through line 37 ahead -o'f the piston to velect an extension ofnthe shock. absorber. to. relieve. the pressure. therein.A With. the pressure ahead of-the piston Ztl -in Atheshockabsorber 16 relieved, the motor unit is adapted' yto" return to its operatire residen- If it is desired -to maintainthe motor unitinitsinopegaf. tive Position fer longer. period. ef-tinrealnieenanisel. holding means is also; provided for the -motor'unit and comprises a pivotal member 59,'mounted on the. y pin member 60 carried by the clamp. -bra'ket[Sprearl Y n of tilt pin 14, The pivotal member 5`9 'ca'rriesa'support bar 61 which is adapted to Vselectively engage ,with or more transverse. grooves 62 provided 'af lthe b i V cowl 2 of the motorvunitwhen the memhrerf?l is prvotedl upwardly in amvertical plane. To effect. disengagement frompthe. mechanical holding means the motor; un raised slightly as requiredneither manually or hy'drau. lical'ly, to lrelease the support bar 61,'from the grooyel 6,2,

lF-IG. 4 shows anotherv embodiment of a pressurewsvup, ply and control arrangement wherebyftheY motor may be raised hydraulically. According to, B1G. 4 a twoposition valve 63 actuated by solenoid-64 isadaptedto, selectively place the'y'supply line'6Skorreturntline k6 6Lfowr reservoir 67 in* communication withconduitk37- totheHAV shock. absorber 16. The solenoid valve 6 3`v isoperated by the battery 68-. andis controlledr by the on-andfoi;` switch v69. actuated byl handle means 70: When, the switch ,69:is open thesolenoid valve 6 3 is. in itsnormal position placing the reservoir return line 66 in communication with'line 37 to the shock absorberYandwtheshockY absorber may then serve to damp any angular momentum imparted to the motor unit.

Upon closing the control switch 69 to tiltrthe motion unitvto a raised inoperative position when desired',- then solenoid 64 is energized and the valve 63 isV actuated to -place the reservoir supply line 65 in communication wi'thline 37 to the shock absorber. Thesolenoid 64.v simultaneouslyrcloses the switch 71- to complete Athecir cuitof pump. motor. 72` whichis run oijofbatteryl to drive the pumpY 73 rdisposed inws'upplyline 65`to ther-e7 by develop the pressure needed for extendingtheshockl` absorber.

Inpthe embodimentofr FIG.V 4,v it is lcontemplated,that the hydraulic system remote. from the shock'absorber, 16 and'including reservoir 67, the pump- 73, and the sole? noid valve 63 together with the pumpnrnotor 7 2A and motor switch 71`m ay be mounted withinthe cowl 2"o`fthe motor unit as represented bythe dashed 1ine74.,V With this arrangement only the on-and-ocontrolgswitch V6,9 isfvdisposed remotely of the motor unit Vat the convenience. of the operator. The arrangement OilersA theadyanta'ge* that thehydraulic system for the shock absorber 16, .re' mains intact l and Yundisturbed ywhen their outboard motor is removed from the boat for anyireasom In FIG., 5, adirigible outboardfvpropulsion; ordr.ive unit 75 is supported from theboat transom 76 andl driven from an .inboard power source, not shown, throughahe, drive shaft 77 Which .extends through thetrarisom.vl The suspension for .the propulsionrunit` 75 .includes.thennount-Y ing bracket 78 rigidly secured to the.tra11sorn 76.v Thel swivel bracket 79l is piyotally ,supported from V,the mounting bracket 78 by means of transversely spaced nhorizontal1 tilt pins 80 providing for pivotal movement offthejrprof, pulsion unit in a vertical plane. 'Forwardly-K. extending andvertically. spaced arms 81 on ,the rpropulsionrlmitare, adapted to receive the. swivelbracket 79g=therebeten and aswivel pin.82 is `disposed generally vertically throught aligned-.holesin thearmsl :andswivel bracket torfpror vide for pivotal movement of the propulsion unit on a generally vertical axis for steering.

The suspension for the propulsion unit 75 includes one or more shock absorbers 16 each mounted between brackets 78 and 79 on pins 83 and 84 provided on the respective brackets. The hydraulic systems of either FIG. 3 or FIG. 4 may be connected to the line 37 in FIG. 5 to adapt the shock absorber for damping any angular momentum imparted to the propulsion unit and for selectively raising and lowering the propulsion unit.

Various modes of carrying out the invention are contemplated as being within the scope of the following claims particularly pointing out and distinctly claiming the subject matter which is regarded as the invention.

I claim:

l. In an outboard propulsion unit for boats, the combination of: a mounting bracket adapted to be secured to the transom of a boat, a propulsion unit, a swivel bracket carrying said propulsion unit and pivotally connected to said mounting bracket on a horizontal transverse axis to provide for tilt of the propulsion unit in a vertical plane between an operative position and an inoperative position, uid pressure damping means interposed and connected between the mounting bracket and swivel bracket and adapted to dissipate a substantial portion of the energy due to sudden pivotal movement of the propulsion unit upon said axis, a source of uid pressure, and conduit means connecting the damping means and the pressure source, said pressure source being adapted to pressurize the damping means when desired to tilt the propulsion unit upon said axis from the operative position to an inoperative position.

2. The combination of claim l wherein the uid pressure damping means is an hydraulic shock absorber adapted to tilt the propulsion unit upon being pressurized when desired.

3. The combination of claim 1 wherein the uid pressure damping means comprises an hydraulic cylinderpiston means and the conduit means is connected to the cylinder means ahead of the piston means.

4. In an outboard motor, the combination of: a clamp bracket adapted to be secured to the transom of a boat, a motor unit, a swivel bracket carrying said motor unit and pivotally connected to the clamp bracket on a horizontal transverse axis to provide for tilt of the motor unit between an opeartive upright position and an inoperative position, hydraulic damping means interposed between and connecting the clamp bracket and swivel bracket to damp a substantial portion of the energy due to sudden pivotal movement of the motor unit upon said axis, a source of lluid pressure, conduit means connecting the damping means and the pressure source, valve means disposed in said conduit means and adapted to selectively control the pressure to the damping means, and means to actuate said valve means and thereby pressurize the damping means when desired to tilt the motor unit upon said axis from the operative position to an inoperative position.

5. The combination of claim 4 wherein the pressure source and valve means are carried on the motor unit providing for an hydraulic system for pressurizing the damping means which remains intact and undisturbed when the outboard motor is removed from the boat.

6. In an outboard motor, the combination of: a clamp bracket adapted to be secured to the transom of a boat, a motor unit, a swivel bracket carrying said motor unit and pivotally connected to the clamp bracket on a horizontal transverse axis to provide `for tilt of the motor unit between an operative upright position and an inoperative position, an hydraulic cylinder-piston means, means pivotally connecting one member of said first named means to the clamp bracket, means pivotally connecting the other member of said first named means to the swivel bracket, said first named means being adapted to extend and thereby damp a substantial portion of the energy due to sudden pivotal movement of the motor unit upon said axis, a source of uid pressure, conduit means connecting the pressure source and the cylinder means ahead of the piston means, valve means disposed in said conduit means and adapted to selectively control the pressure to the cylinder means, and means to actuate said valve means and thereby pressurize and extend said iirst named means when desired to tilt the motor unit upon said axis from the operative position to an inoperative position.

7. In an outboard motor, the combination of: a clamp bracket adapted to 'be secured to the transon of a boat, a motor unit, a swivel bracket carrying said motor unit and pivotally connected to the clamp bracket on a horizontal transverse axis to provide for tilt of the motor unit between an operative upright position and an inoperative position, hydraulic damping means interposed between and connecting the clamp bracket and swivel bracket to damp a substantial portion of the energy due to sudden pivotal movement of the motor unit upon said axis, a. source of iluid pressure, conduit means connecting the damping means and the pressure source, valve means disposed in said conduit means and adapted to selectively control the pressure to the damping means, a solenoid for operating the valve means, a source of electrical energy Ifor said solenoid, and switch means to control operation of the solenoid -to selectively actuate the valve means and thereby pressuze the damping means to tilt the motor unit upon said axis from the operative position to an inoperative position.

8. The combination of claim 7 wherein the pressure source and the solenoid operated valve means are carried on the motor unit and remotely from. the switch means for controlling the solenoid.

9. In a marine propulsion mechanism, the combination with mounting bracket means adapted to be secured to a boat and a propulsion unit pivotally connected to the mounting bracket means on a horizontal transverse axis to provide for tilt movement of the unit in a generally vertical plane between an operative posit-ion and an inoperative position, liuid pressure damping means interposed and connected between the mounting bracket means and propulsion unit and adapted to dissipate a substantial portion of t-he energy due to sudden pivotal movement of the propulsion unit upon said axis, a source of iiuid pressure, and conduit means connecting the damping means and the pressure source, said pressure source being adapted to pressurize the damping means when desired to tilt the propulsion unit upon said axis from the operative position to an inoperative position.

No referenc cited. 

